1. Field of the Invention
This invention relates generally to machine tools, and more particularly to a turning machine which simultaneously removes material from both the outer and inner cylindrical surfaces of rings.
2. Description of the Prior Art
A conventional practice for machining rings has been to use a chucker which grips the inner cylindrical surface of a ring while it machines material off the outer cylindrical surface, or grips the outer cylindrical surface while it machines material from the inner cylindrical surface. The use of such machines requires that, before the workpiece is gripped, some reasonable effort be made to clean the gripped surface and the grippers themselves so as to be sure that the workpiece is properly positioned and centered on the axis of the turning machine. After either the outer surface has been machined or the inner surface has been machined, a part handling step is required in addition to the step of cleaning the other surface to be gripped and the grippers to grip it.
Several of the above-mentioned steps can be eliminated by using a machine which, instead of gripping the outer cylindrical surface or the inner cylindrical surface, clamps the ring between the edges, and machines both the inside diameter (I.D.) and the outside diameter (O.D.) simultaneously. But such machines as known to me prior to the present invention, have relied on a double armed pick-up and placing device to place the ring in position to be machined, and center it, and remove the ring from the machine when the machining is finished. In addition, it has not been feasible to remove the boring tool from the workpiece without leaving some mark on the surface. Also, it has been necessary to gauge the machined part manually. Therefore, it is desirable to overcome these problems associated with the prior art equipment.